Precision Chemistry最新文献_第8页

Enhanced Hydrogen Adsorption on In₂O₃(111) via Oxygen Vacancy Engineering. 氧空位工程增强In2O3（111）对氢的吸附

Precision Chemistry Pub Date : 2025-03-20 eCollection Date: 2025-06-23 DOI: 10.1021/prechem.5c00005

Yishui Ding, Jie Chen, Haihong Zheng, Yalong Jiang, Linbo Li, Xiangrui Geng, Xu Lian, Lu Yang, Ziqi Zhang, Kelvin Hongliang Zhang, Hexing Li, JianQiang Zhong, Wei Chen

{"title":"Enhanced Hydrogen Adsorption on In2O3(111) via Oxygen Vacancy Engineering.","authors":"Yishui Ding, Jie Chen, Haihong Zheng, Yalong Jiang, Linbo Li, Xiangrui Geng, Xu Lian, Lu Yang, Ziqi Zhang, Kelvin Hongliang Zhang, Hexing Li, JianQiang Zhong, Wei Chen","doi":"10.1021/prechem.5c00005","DOIUrl":"10.1021/prechem.5c00005","url":null,"abstract":"The emergence of In2O3 as an efficient catalyst for selective hydrogenation has attracted significant attention. However, the mechanism of hydrogen (H2) dissociation on In2O3 remains experimentally elusive. In this work, we show that the interaction of H2 with In2O3 is strongly influenced by the presence of oxygen vacancies. Using a combination of in situ near-ambient-pressure X-ray photoelectron spectroscopy (NAP-XPS), ultraviolet photoelectron spectroscopy (UPS), infrared reflection absorption spectroscopy (IRRAS), and density functional theory (DFT) calculations, we systematically investigated the interaction of H2 on well-defined oxidized In2O3(111) and partially reduced In2O3-x (111) surfaces. Our results reveal that H2 dissociates and adsorbs as hydroxyl groups (OH), which are exclusively stabilized on the In2O3-x (111) surface. The adsorbed hydrogen species act as electron donors, contributing to interfacial electron accumulation near the surface and inducing downward band bending. DFT calculations further indicate that oxygen vacancies in In2O3-x (111) are critical for facilitating the heterolytic dissociation of H2, leading to the stabilization of In-H and OH species. These findings provide valuable implications for the catalytic behavior of indium oxide in hydrogenation and hydrogen-involved redox reactions.","PeriodicalId":29793,"journal":{"name":"Precision Chemistry","volume":"3 6","pages":"337-347"},"PeriodicalIF":0.0,"publicationDate":"2025-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12188397/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144508680","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Enhanced Hydrogen Adsorption on In2O3(111) via Oxygen Vacancy Engineering 氧空位工程增强In2O3（111）对氢的吸附

Precision Chemistry Pub Date : 2025-03-19 DOI: 10.1021/prechem.5c0000510.1021/prechem.5c00005

Yishui Ding, Jie Chen, Haihong Zheng, Yalong Jiang, Linbo Li, Xiangrui Geng, Xu Lian, Lu Yang, Ziqi Zhang, Kelvin Hongliang Zhang, Hexing Li, JianQiang Zhong* and Wei Chen*,

{"title":"Enhanced Hydrogen Adsorption on In2O3(111) via Oxygen Vacancy Engineering","authors":"Yishui Ding, Jie Chen, Haihong Zheng, Yalong Jiang, Linbo Li, Xiangrui Geng, Xu Lian, Lu Yang, Ziqi Zhang, Kelvin Hongliang Zhang, Hexing Li, JianQiang Zhong* and Wei Chen*, ","doi":"10.1021/prechem.5c0000510.1021/prechem.5c00005","DOIUrl":"https://doi.org/10.1021/prechem.5c00005https://doi.org/10.1021/prechem.5c00005","url":null,"abstract":"The emergence of In2O3 as an efficient catalyst for selective hydrogenation has attracted significant attention. However, the mechanism of hydrogen (H2) dissociation on In2O3 remains experimentally elusive. In this work, we show that the interaction of H2 with In2O3 is strongly influenced by the presence of oxygen vacancies. Using a combination of in situ near-ambient-pressure X-ray photoelectron spectroscopy (NAP-XPS), ultraviolet photoelectron spectroscopy (UPS), infrared reflection absorption spectroscopy (IRRAS), and density functional theory (DFT) calculations, we systematically investigated the interaction of H2 on well-defined oxidized In2O3(111) and partially reduced In2O3–x(111) surfaces. Our results reveal that H2 dissociates and adsorbs as hydroxyl groups (OH), which are exclusively stabilized on the In2O3–x(111) surface. The adsorbed hydrogen species act as electron donors, contributing to interfacial electron accumulation near the surface and inducing downward band bending. DFT calculations further indicate that oxygen vacancies in In2O3–x(111) are critical for facilitating the heterolytic dissociation of H2, leading to the stabilization of In–H and OH species. These findings provide valuable implications for the catalytic behavior of indium oxide in hydrogenation and hydrogen-involved redox reactions.","PeriodicalId":29793,"journal":{"name":"Precision Chemistry","volume":"3 6","pages":"337–347 337–347"},"PeriodicalIF":0.0,"publicationDate":"2025-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/epdf/10.1021/prechem.5c00005","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144338105","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Controlled Synthesis of SnO2 Nanocrystals with Tunable Band Gaps 带隙可调SnO2纳米晶体的受控合成

IF 6.2

Precision Chemistry Pub Date : 2025-03-16 DOI: 10.1021/prechem.4c00107

Can Li, Xin Shu, Jun Zhang, Joseph Delgado, Prabhu Bharathan, Yuxuan Wang, Chenyu Wang and Jiye Fang*,

{"title":"Controlled Synthesis of SnO2 Nanocrystals with Tunable Band Gaps","authors":"Can Li, Xin Shu, Jun Zhang, Joseph Delgado, Prabhu Bharathan, Yuxuan Wang, Chenyu Wang and Jiye Fang*, ","doi":"10.1021/prechem.4c00107","DOIUrl":"https://doi.org/10.1021/prechem.4c00107","url":null,"abstract":"Tin(IV) oxide nanocrystals (SnO2 NCs) have significant potential in various applications, with their performance closely related to their band gap. The band gap is influenced by the size and shape of the NCs, which can be precisely controlled by adjusting reaction conditions. In this study, we present deliberately designed synthesis protocols to produce high-quality SnO2 NCs with tunable band gaps using different methods. Key factors affecting the synthesis include control of the oxidizing agent, reaction temperature, solvent selection, and reaction time optimization. The resulting NCs were characterized by using TEM, XRD, XPS, and optical spectroscopy. Notably, SnO2 NCs synthesized by controlling the oxidizing agent (air injection) in a hot organic solution were smaller in size and exhibited abundant oxygen vacancies. In contrast, extending the reaction time or using ethanol as a solvent in hydrothermal systems facilitated larger spherical or rod-like SnO2 NCs with fewer oxygen vacancies. Further analysis of the band gap and valence band maximum energy revealed that the abundant vacancies in SnO2 NCs synthesized with the air-controlled hot organic solution method resulted in a narrower band gap and an upshifted valence band. These synthetic strategies illustrate the potential for deliberately designing SnO2 NCs with optimized electronic structures for various applications.","PeriodicalId":29793,"journal":{"name":"Precision Chemistry","volume":"3 8","pages":"463–469"},"PeriodicalIF":6.2,"publicationDate":"2025-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/pdf/10.1021/prechem.4c00107","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144892654","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Improving the Cold-Start Performance of Proton Exchange Membrane Fuel Cells via Precision Engineering of Key Materials. 关键材料精细化工程提高质子交换膜燃料电池冷启动性能。

Precision Chemistry Pub Date : 2025-03-14 eCollection Date: 2025-04-28 DOI: 10.1021/prechem.4c00079

Zhiyuan Ge, Shuying Xu, Xiaoyang Fu, Zipeng Zhao

{"title":"Improving the Cold-Start Performance of Proton Exchange Membrane Fuel Cells via Precision Engineering of Key Materials.","authors":"Zhiyuan Ge, Shuying Xu, Xiaoyang Fu, Zipeng Zhao","doi":"10.1021/prechem.4c00079","DOIUrl":"https://doi.org/10.1021/prechem.4c00079","url":null,"abstract":"Proton exchange membrane fuel cells (PEMFCs) have emerged as important zero-emission power sources due to their efficiency and eco-friendly characteristics. A critical feature required for their widespread adoption is the performance of low-temperature cold start. However, at subzero degrees Celsius, the freezing of the produced water can hinder or even lead to failure of the fuel cell start-up process. To successfully achieve a cold start under such conditions, the PEMFC must rapidly and reliably transition from a fully cooled state to a stable operating condition. Various improvements have been focused on the system engineering aspect to address this challenge, yet many of these methods come with their drawbacks. This paper reviews the recent progress of the PEMFC cold start from the perspective of key materials engineering. It provides a detailed summary of how the proton exchange membrane (PEM), catalyst layer, microporous layer (MPL), and gas diffusion layer (GDL) affect the cold-start performance. Further analysis reveals that the fundamental mechanisms of improving cold-start performance can be summarized into three aspects: increasing the ratio of water bound in the ionomer, hindering the transformation process from supercooled water to ice, improving the removal of supercooled water, or ensuring it is transported to the outside of the membrane electrode assembly (MEA) before it gets frozen. By precisely regulating these key components, it is possible to develop a simple and energy-efficient solution for improving the cold start performance of the PEMFC.","PeriodicalId":29793,"journal":{"name":"Precision Chemistry","volume":"3 4","pages":"172-186"},"PeriodicalIF":0.0,"publicationDate":"2025-03-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12042135/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144049844","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Improving the Cold-Start Performance of Proton Exchange Membrane Fuel Cells via Precision Engineering of Key Materials 关键材料精细化工程提高质子交换膜燃料电池冷启动性能

Precision Chemistry Pub Date : 2025-03-14 DOI: 10.1021/prechem.4c0007910.1021/prechem.4c00079

Zhiyuan Ge, Shuying Xu, Xiaoyang Fu* and Zipeng Zhao*,

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引用次数: 0

Synthesis of Alternatively-Twisted Nanographenes by Semi-Deprotection-Induced Cyclization 半脱保护诱导环化法合成交替扭曲纳米石墨烯

Precision Chemistry Pub Date : 2025-03-13 DOI: 10.1021/prechem.5c0000110.1021/prechem.5c00001

Zhenxun Xu, Suriguga Meng, Zhiyu Zhang, Shuqin Han*, Fenghua Bai*, Yanping Dong, Yoshifumi Hashikawa* and Chaolumen*,

{"title":"Synthesis of Alternatively-Twisted Nanographenes by Semi-Deprotection-Induced Cyclization","authors":"Zhenxun Xu, Suriguga Meng, Zhiyu Zhang, Shuqin Han*, Fenghua Bai*, Yanping Dong, Yoshifumi Hashikawa* and Chaolumen*, ","doi":"10.1021/prechem.5c0000110.1021/prechem.5c00001","DOIUrl":"https://doi.org/10.1021/prechem.5c00001https://doi.org/10.1021/prechem.5c00001","url":null,"abstract":"Twisted nanographenes (NGs) are currently attracting a lot of attention owing to their geometrical and electronic structures that differ substantively from conventional planar and nonplanar NGs, while the strategic synthesis of twisted NGs is still a topic of interest because the products are often interconvertible among unidirectionally, alternatively, or randomly twisted geometries and otherwise obtained as a mixture of them. Herein, we report the conformationally specific synthesis of twisted NGs where the geometry was reinforced by introducing 1,4-dioxane rings at a K-region of a central pyrene core that bears a large contortion. The 1,4-dioxane rings were generated by semi-deprotection, of tetraoxa[4.4.4]propellanes in precursor molecules, which were confirmed to be engaged in forming C–C bonds via a Friedel–Crafts type mechanism. The large contortion within the pyrene core causes a narrowed HOMO–LUMO gap on account of unusual pz-lobe overlap between +z and −z sides, giving rise to red emission with a high quantum yield of 94% as well as stable redox processes of 2e– uptake/release.","PeriodicalId":29793,"journal":{"name":"Precision Chemistry","volume":"3 5","pages":"289–294 289–294"},"PeriodicalIF":0.0,"publicationDate":"2025-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/epdf/10.1021/prechem.5c00001","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144133897","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Correction to "Stepwise Chemical Reduction of [4]Cyclo[4]helicenylene: Stereo Transformation and Site-Selective Metal Complexation". 对“[4]环[4]螺旋炔的逐步化学还原：立体转化和选择性金属络合”的修正。

Precision Chemistry Pub Date : 2025-03-13 eCollection Date: 2025-04-28 DOI: 10.1021/prechem.5c00027

Zheng Zhou, Yong Yang, Jianwei Liang, Sota Sato, Zhenyi Zhang, Zheng Wei

引用次数: 0

Correction to “Stepwise Chemical Reduction of [4]Cyclo[4]helicenylene: Stereo Transformation and Site-Selective Metal Complexation” 对“[4]环[4]螺旋炔的逐步化学还原：立体转化和选择性金属络合”的修正

Precision Chemistry Pub Date : 2025-03-13 DOI: 10.1021/prechem.5c0002710.1021/prechem.5c00027

Zheng Zhou*, Yong Yang*, Jianwei Liang, Sota Sato, Zhenyi Zhang and Zheng Wei,

引用次数: 0

Synthesis of Alternatively-Twisted Nanographenes by Semi-Deprotection-Induced Cyclization. 半脱保护诱导环化法合成交替扭曲纳米石墨烯。

Precision Chemistry Pub Date : 2025-03-13 eCollection Date: 2025-05-26 DOI: 10.1021/prechem.5c00001

Zhenxun Xu, Suriguga Meng, Zhiyu Zhang, Shuqin Han, Fenghua Bai, Yanping Dong, Yoshifumi Hashikawa, Chaolumen

{"title":"Synthesis of Alternatively-Twisted Nanographenes by Semi-Deprotection-Induced Cyclization.","authors":"Zhenxun Xu, Suriguga Meng, Zhiyu Zhang, Shuqin Han, Fenghua Bai, Yanping Dong, Yoshifumi Hashikawa, Chaolumen","doi":"10.1021/prechem.5c00001","DOIUrl":"10.1021/prechem.5c00001","url":null,"abstract":"Twisted nanographenes (NGs) are currently attracting a lot of attention owing to their geometrical and electronic structures that differ substantively from conventional planar and nonplanar NGs, while the strategic synthesis of twisted NGs is still a topic of interest because the products are often interconvertible among unidirectionally, alternatively, or randomly twisted geometries and otherwise obtained as a mixture of them. Herein, we report the conformationally specific synthesis of twisted NGs where the geometry was reinforced by introducing 1,4-dioxane rings at a K-region of a central pyrene core that bears a large contortion. The 1,4-dioxane rings were generated by semi-deprotection, of tetraoxa[4.4.4]-propellanes in precursor molecules, which were confirmed to be engaged in forming C-C bonds via a Friedel-Crafts type mechanism. The large contortion within the pyrene core causes a narrowed HOMO-LUMO gap on account of unusual p z -lobe overlap between +z and -z sides, giving rise to red emission with a high quantum yield of 94% as well as stable redox processes of 2e- uptake/release.","PeriodicalId":29793,"journal":{"name":"Precision Chemistry","volume":"3 5","pages":"289-294"},"PeriodicalIF":0.0,"publicationDate":"2025-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12117430/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144183352","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The Art of Building Small. 小建筑的艺术。

Precision Chemistry Pub Date : 2025-03-12 eCollection Date: 2025-03-24 DOI: 10.1021/prechem.5c00023

Ben L Feringa

引用次数: 0